Many vehicles today have electric power steering systems. Electric power steering (EPS) systems typically use an electric motor to provide a steering assist to a driver of the vehicle, thereby reducing effort by the driver in steering the vehicle. In this invention, a control algorithm is implemented with an existing control system to aggressively alleviate steering wheel vibrations.
Smooth road shake (SRS) is one of the vibrations leading to customers complaints. SRS is caused by external excitation such as irregular road surfaces and internal periodic excitation such as tire/wheel imbalance, tire irregularities, brake rotor imbalance and lack of precision piloting of the rotating members. The SRS condition occurs in both EPS and HPS (Hydraulic Power Steering) systems. The EPS system or HPS system with active control devices provides an opportunity to change the control algorithm in the ECU (electronic control unit) to mitigate SRS.
Accordingly, it is desirable to improve the current EPS control system to reduce the steering wheel vibration of the vehicles. It is further desired to provide an improved system for such control of motor current in vehicles. Furthermore, other desirable features and characteristics of the present invention will be apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.